Management of a database system

ABSTRACT

A method, system, and computer program product to manage a database is disclosed. The method, system, and computer program product may include structuring the database to have a first table having an index and a second table. A first key of the first table may be related to a second key of the second table. The method, system, and computer program product may include creating an entry locator in the index. The method, system, and computer program product may include maintaining an association between the second key of the second table and the entry locator of the index.

TECHNICAL FIELD

This disclosure relates generally to computing systems and, moreparticularly, relates to database management systems.

BACKGROUND

Databases are used to store information for numerous types ofapplications. Examples include various industrial, commercial,technical, scientific, and educational applications. Database managementsystems (DBMSs) are a typical mechanism for accessing data stored in adatabase. DBMSs are typically configured to separate the process ofstoring data from accessing, manipulating, or using data stored in adatabase. DBMSs may benefit from system resource savings andefficiencies.

SUMMARY

Aspects of the disclosure may include a method, system, and computerprogram product to manage a database. The method, system, and computerprogram product may include structuring the database to have a firsttable having an index and a second table. A first key of the first tablemay be related to a second key of the second table. The method, system,and computer program product may include creating an entry locator inthe index. The method, system, and computer program product may includemaintaining an association between the second key of the second tableand the entry locator of the index.

Aspects of the disclosure may include a database. The database mayinclude a dimension table and a fact table. The dimension table may havea primary key. The fact table may have a foreign key. An index on thefact table may exist. An entry locator may be created in the index. Anassociation may be maintained between the primary key of the dimensiontable and the entry locator of the index. Maintaining the associationbetween the primary key of the dimension table and the entry locator ofthe index may keep the entry locator updated. In embodiments, theassociation may be maintained in response to maintenance to thedimension table. In embodiments, the association may be maintained inresponse to a query to the database. In embodiments, the index may be anencoded vector index. In embodiments, the entry locator may be a columnof a symbol table. Aspects of the disclosure may save system resources.Less paging of objects may occur. The dimension table may or may notneed to be checked regarding the primary key and a change may be madedirectly to the fact table. Fewer indexes may be created and fewerindexes may need to be maintained. A task may be efficient or performwell because of fewer indexes needing to be accessed for the task.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example representation of a computer systemconnected to a client computer via a network according to an embodiment;

FIG. 2 illustrates an example database management system (DBMS)according to an embodiment;

FIG. 3 illustrates a prior art example of a star schema with multipledimension tables and a fact table;

FIG. 4 illustrates a database according to an embodiment;

FIG. 5 illustrates an index according to an embodiment;

FIG. 6 illustrates a symbol table according to an embodiment; and

FIG. 7 is a flowchart illustrating an operation to manage a databaseaccording to an embodiment.

DETAILED DESCRIPTION

A database administrator may desire to run a query or maintain thedatabase by adding, deleting, or changing a record in the database.Indexes may need to be created, to be maintained, or to perform tasks.The database administrator may have a small temporal window. Whenassociated with a large amount of data, these activities may take anamount of time and performance overhead such as system resources thatare not insignificant. It may be desirable to create fewer indexes. Itmay be desirable to have fewer indexes to maintain. It may be desirableto perform less processing.

Aspects of the disclosure may include a database. The database mayinclude a dimension table and a fact table. The dimension table may havea primary key. The fact table may have a foreign key. An index on thefact table may exist. An entry locator may be created in the index. Anassociation may be maintained between the primary key of the dimensiontable and the entry locator of the index. Maintaining the associationbetween the primary key of the dimension table and the entry locator ofthe index may keep the entry locator updated. In embodiments, theassociation may be maintained in response to maintenance to thedimension table. In embodiments, the association may be maintained inresponse to a query to the database. In embodiments, the index may be anencoded vector index. In embodiments, the entry locator may be a columnof a symbol table. Aspects of the disclosure may save system resources.Less paging of objects may occur. The dimension table may or may notneed to be checked regarding the primary key and a change may be madedirectly to the fact table. Fewer indexes may be created and fewerindexes may need to be maintained. A task may be efficient or performwell because of fewer indexes needing to be accessed for the task.

FIG. 1 illustrates an example representation of a computer system 100connected to one or more client computers 160 via a network 155,according to some embodiments. For the purposes of this disclosure,computer system 100 may represent practically any type of computer,computer system, or other programmable electronic device, including butnot limited to, a client computer, a server computer, a portablecomputer, a handheld computer, an embedded controller, etc. In someembodiments, computer system 100 may be implemented using one or morenetworked computers, e.g., in a cluster or other distributed computingsystem.

The computer system 100 may include, without limitation, one or moreprocessors (CPUs) 105, a network interface 115, an interconnect 120, amemory 125, and a storage 130. The computer system 100 may also includean I/O device interface 110 used to connect I/O devices 112, e.g.,keyboard, display, and mouse devices, to the computer system 100.

Each processor 105 may retrieve and execute programming instructionsstored in the memory 125 or storage 130. Similarly, the processor 105may store and retrieve application data residing in the memory 125. Theinterconnect 120 may transmit programming instructions and applicationdata between each processor 105, I/O device interface 110, networkinterface 115, memory 125, and storage 130. The interconnect 120 may beone or more busses. The processor 105 may be a single central processingunit (CPU), multiple CPUs, or a single CPU having multiple processingcores in various embodiments. In one embodiment, a processor 105 may bea digital signal processor (DSP).

The memory 125 may be representative of a random access memory, e.g.,Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM),read-only memory, or flash memory. The storage 130 may be representativeof a non-volatile memory, such as a hard disk drive, solid state device(SSD), or removable memory cards, optical storage, flash memory devices,network attached storage (NAS), or connections to storage area network(SAN) devices, or other devices that may store non-volatile data. Thenetwork interface 115 may be configured to transmit data via thecommunications network 155.

The memory 125 may include a database management system (DBMS) 135, aresult set 140, a query 145, and applications 150. Although theseelements are illustrated as residing in the memory 125, any of theelements, or combinations thereof, may reside in the storage 130 orpartially in the memory 125 and partially in the storage 130. Each ofthese elements will be described in greater detail in accordance withFIG. 2.

The network 155 may be any suitable network or combination of networksand may support any appropriate protocol suitable for communication ofdata and/or code to/from the server computer system 100 and the clientcomputer system 160. In some embodiments, the network 155 may supportwireless communications. In other embodiments, the network 155 maysupport hardwired communications. The network 155 may be the Internetand may support Internet Protocol in some embodiments. In otherembodiments, the network 155 may be implemented as a local area network(LAN) or a wide area network (WAN). The network 155 may also beimplemented as a cellular data network. Although the network 155 isshown as a single network in the figures, one or more networks of thesame or different types may be included.

The client computer system 160 may include some or all of the hardwareand software elements of the computer system 100 previously described.As shown, there may be one or more client computers 160 connected to thecomputer system 100 via the network 155. In some embodiments, one ormore client computers 160 may send a query 145 by network 155 tocomputer system 100 and receive a result set 140.

FIG. 2 illustrates an example database management system (DBMS) 135. TheDBMS 135 may include a parser 210, an optimizer 220, an execution engine230, and a database 232. The parser 210 may receive a database query 145from an application 150. In some embodiments, the database query 145 maybe in the form of a Structured Query Language (SQL) statement. Theparser 210 may generate a parsed statement 215. The parser 210 may sendthe parsed statement 215 to an optimizer 220. The optimizer 220 mayattempt to optimize the parsed statement. In some embodiments,optimizing may improve the performance of the database query 145 by, forexample, reducing the amount of time it takes to provide a user with aresponse. The optimizer 220 may generate an execution plan 246, whichmay be maintained in a query plan cache 245, according to someembodiments. The query plan cache 245 may include one or more executionplans 246, including the current execution plan as well as previouslyused execution plans. Once an execution plan 246 is generated, theexecution plan 246 may be sent to the execution engine 230. Theexecution engine 230 may execute the query 145. Executing the query 145may include finding and retrieving data in the database tables 235 thatsatisfies the criteria supplied in the query 145. The execution engine230 may store the data returned matching the query 145 in a result set140. The DBMS 135 may return the result set 140 to an application 150,such as the application in which the database query 145 was generated,as a response to the database query 145.

A database 232 may include one or more tables 235 and, in someembodiments, one or more indexes 240. A database table 235 may organizedata into rows and columns. Each row of a database table 235 maycorrespond to an individual entry, a tuple, or a record in the database232. A column may define what is stored in each entry, tuple, or record.In some embodiments, columns of a table 235 may also be referred to asfields or attributes. Each table 235 within the database 232 may have aunique name. Each column within a table 235 may also have a unique name.A row, tuple, or record, however, within a particular table 235 may notbe unique, according to some embodiments. A database 232 may alsoinclude one or more indexes 240. An index 240 may be a data structurethat may inform the DBMS 135 of the location of a particular recordwithin a table 235 if given a particular indexed column value. In someembodiments, the execution engine 230 may use the one or more indexes240 to locate data within a table 235. In other embodiments, theexecution engine 230 may scan the tables 235 without using an index 240.

FIG. 3 illustrates a prior art example of a star schema 302 withmultiple dimension tables 304, 306, and 308 and a fact table 310. Thefact table 310 includes sales data, wherein each record includesinformation on the amount sold in the AMOUNT column 312; a timeidentifier (TID) is included for the time of sale in the TID column 314;a product identifier (PID) is included for the product sold in the PIDcolumn 316; and a geographic identifier (GID) is included for thelocation of the sale, e.g., store location, in the GID column 318. Thedimension tables 304, 306, and 308 provide attributes on the TID 314,PID 316, and GID 318 columns in the fact table.

The primary key columns of each of the dimension tables 304, 306, 308are the TID column 320, PID column 328, and GID column 336,respectively. The columns 314, 316, and 318 in the fact table 310 areforeign keys that relate or correspond to primary keys 320, 328, and 336of the dimension tables 304, 306, 308 that provide attributes on thedata in the fact table 310. For instance dimension table 304 providesattributes for each possible TID value, including month information incolumn 322, quarter of the TID in the quarter column 324, and the yearof the TID in the year column 326. Dimension table 306 provides productattributes for each PID value, including the product item in item column330, the class of the product in the class column 332, and the inventorylocation of the product in inventory column 334. The dimension table 308provides attributes for each possible GID value, including the city ofthe GID in the city column 338, the geographical region in the regioncolumn 340, and the country in the country column 342.

FIG. 4 illustrates a database 400 according to an embodiment. Thedatabase 400 may include a first table which may be a fact table 435.The fact table 435 may have a first key which may be a foreign key. Thedatabase 400 may include a second table which may be a dimension table470. In embodiments, the dimension table 470 may be a significantdistance from the fact table 435 or its indexes. The significantdistance may be a geographic distance (e.g., different time zone) andmay have latency implications (e.g., temporal delay). Multiple dimensiontables are illustrated as 470A, 470B, 470C, 470D. Each dimension table470 may have a second key which may be a primary key. Each foreign keyof the fact table 435 may be related to the primary key of eachdimension table 470.

An index 440 on the fact table 435 may exist. Multiple indexes areillustrated as encoded vector indexes (EVIs) 440A, 440B, 440C, 440D asan example. An EVI is a type of index providing access to a table byassigning codes to distinct key values. EVIs can be used to processlarge amounts of data efficiently because of their compact size andrelative simplicity. The indexes 440 need not be EVIs, but may be EVIsin some embodiments.

An association 495, illustrated as associations 495A, 495B, 495C, 495D,may be maintained between the primary key of the dimension table 470 andaspects of the database 400 which may include at least one of theindexes 440 and the fact table 435. Maintaining the association 495 mayinclude keeping updated an element in the index 440 with informationpertaining to the second key of the dimension table 470. In embodiments,the association 495 may be of the significant distance between thedimension table 470 and the fact table 435 or the indexes 440. Inembodiments, for example, the association 495A may be maintained betweenthe primary key of the dimension table 470A and aspects of the index440A. In embodiments, the association 495 may be maintained in responseto maintenance to the dimension table 470. In embodiments, theassociation 495 may be maintained in response to a query 145 to thedatabase 400. In embodiments, the association 495 may be maintained inresponse to a temporal element such as a certain time of day. Inembodiments, the association 495 may be maintained in response to arefresh period such as a length of time since the association 495 waslast maintained.

FIG. 5 illustrates the index 440A according to an embodiment. Aspects ofFIG. 5 may be similar or the same as FIG. 4. EVI 440A may include asymbol table 541 and a vector 542. The vector 542 may contain a row forevery record in the fact table 435 for which EVI 440A is an index. Eachvector row corresponds to a fact table 435 record, and contains a codefor the key value contained in the field of the fact table 435. Thesymbol table 541 may have a record for each particular key value thatcan be found for a field in the fact table 435 for which EVI 440A is anindex. The symbol table 541 may include a translation from theparticular key value to a code, as well as the count of how many recordsin the fact table 435 contain the key value. Using the code field, thesymbol table 541 may be used to decode the vector 542.

FIG. 6 illustrates the symbol table 541 according to an embodiment.Aspects of FIG. 6 may be similar or the same as FIG. 4 and FIG. 5.Contents of the symbol table 541 are provided as an example. The keyvalue may be a product identifier (PID). The code, the first row, thelast row, and the count may be statistics similar to that described inrelation to FIG. 5. In embodiments, the symbol table 541 may have anassociation with the primary key of the dimension table 470A.

The symbol table 541 may include an entry locator 601. In embodiments,the entry locator 601 may be elsewhere in the index that is EVI 440A. Aspart of the symbol table 541, the entry locator 601 may exist as a fieldor column. In embodiments, the entry locator may be created by derivinginformation related to the dimension table. In embodiments, theinformation related to the dimension table may be a relative recordnumber (RRN).

The entry locator 601 may have the association 495 (see FIG. 4. and FIG.5) with the primary key of the dimension table 470A. A particularassociation shown in FIG. 6 represents a relative record number (RRN) ofthe key value in the dimension table 470A. The primary key of thedimension table 470A may be a significant distance from the entrylocator 601. In embodiments, the association may be maintained inresponse to maintenance to the dimension table 470A. The associationbetween the primary key of the dimension table 470A and the entrylocator 601 may include flow from the dimension table 470A to the entrylocator 601. Flow may include at least one of a broadcast,communication, connection, conveyance, correspondence, message,publication, and transmission. The flow may be in response tomaintenance (e.g., addition, deletion, change) on the dimension table470A. Other embodiments are contemplated, including but not limited tothe association being maintained in response to a query 145 to thedatabase 400.

At least one of the entry locator 601 and maintaining the association495 may save system resources or enhance efficiency. Without the entrylocator 601 and maintaining the association 495, a task such as adding anew product to the fact table 435 may require the fact table 435 or oneof its indexes 440 to effectively reach out across the significantdistance to the dimension table 470 for data that then may need to besent back across the significant distance to the fact table 435 or oneof its indexes 440. The significant distance in that scenario may havelatency implications. A substantial cost in resources or efficiency canincur for information traveling the significant distance to and from,for example, the fact table 435 of a sales kiosk of a store and, forexample, the dimension table 470A of a cloud-based server when thesignificant distance separates the sales kiosk from the cloud-basedserver by a time-zone. On the other hand, with at least one of the entrylocator 601 and maintaining the association 495, the significantdistance may be traveled fewer times, at more efficient times, etc. Forexample, information may travel from the dimension table 470 to theindex 440 at a certain time of day, when information in the dimensiontable 470 changes, etc. Thus, aspects of the disclosure may reducepotential negative impacts due to latency time over the significantdistance. In the foregoing, when the sales kiosk reaches for theinformation it need only look to the entry locator 601 which may be inthe symbol table 541 in the EVI 440A. Such information may be at thesales kiosk or in the store. The cloud-based server the time zone awaymay or may not need to be involved in as many instances.

For example as represented in FIG. 6, key value “SM39K58,” which may bethe product identifier (PID) for a seed corn hybrid, has “1” for theentry locator 601. Thus, the PID “SM39K58” may be in RRN “1” of thedimension table 470A (which may include attributes of specific seed cornhybrids) having a primary key PID. A task (e.g., add new product),query, or modification associated with the fact table 435 (e.g., salestransactions) related to EVI 440A may or may not then need to interactwith the dimension table 470A. In particular, the case of notinteracting with the dimension table 470A may save system resources orenhance efficiency.

Row addition 602 of the symbol table 541 represents in the symbol table541 a distinct value of an example new row. In embodiments, the examplenew row may have been added to the dimension table 470A in RRN “97” witha PID “SM39K52” for the distinct value of a new seed corn hybrid for anupcoming planting season. Including row addition 602 is an update to thesymbol table 541 which may occur before a user (e.g., seed cornsalesman) of the fact table 435 attempts to use the distinct value“SM39K52” for the PID. In embodiments, the distinct value of the newseed corn hybrid with the PID “SM39K52” may be added to the symbol table541. The symbol table 541 may indirectly check for uniqueness. If“SM39K52” already existed in the symbol table 541, an error may be sentto an application or the user attempting to insert a duplicate key. Eventhough the current count for the distinct value in the row addition 602is “0,” the row addition 602 is ready for use by the fact table 435 or aquery 145 and may or may not need to interact with the dimension table470A upon such requested use by the fact table 435 or the query 145. Theresult may include a cost savings in forms of saved system resources,enhanced efficiency, etc.

FIG. 7 is a flowchart illustrating an operation 700 to manage a databaseaccording to an embodiment. The operation 700 may manage a database. Theoperation 700 may begin at block 701. The database may be structured tohave a first table having an index and a second table at block 710. Thefirst table may be a fact table. The index may be an encoded vectorindex. The second table may be a dimension table. The first table mayhave a first key. The first key may be a foreign key. The first key ofthe first table may be related to a second key of the second table. Thefirst key may correspond to the second key. The second key may be aprimary key.

An entry locator may be created in the index at block 720. The entrylocator may be a column of a symbol table. In embodiments, the entrylocator may be created by deriving information related to the secondtable. In embodiments, the information related to the second table maybe a relative record number.

An association between the second key of the second table and the entrylocator in the index may be maintained at block 730. Maintaining theassociation between the second key of the second table and the entrylocator in the index may include keeping updated the entry locator inthe index with information pertaining to the second key of the secondtable. Put differently, maintaining the association between the primarykey of the second table and the entry locator of the index may keep theentry locator updated. The association between the second key and theentry locator may be maintained in response to maintenance to the secondtable. Maintenance to the second table may include at least one of anaddition, a deletion, and a change. The association between the secondkey and the entry locator may be maintained in response to a query tothe database.

The operation may conclude at block 799. Aspects of the operation 700may save system resources. Less paging of objects may occur. The secondtable may or may not need to be checked regarding the second key and achange may be made directly to the first table. Fewer indexes may becreated and fewer indexes may need to be maintained. A task may beefficient or perform well because of fewer indexes needing to beaccessed for the task. In addition to embodiments described above, otherembodiments having fewer operational steps, more operational steps, ordifferent operational steps are contemplated. Also, some embodiments mayperform some or all of the above operational steps in a different order.

In the foregoing, reference is made to various embodiments. It should beunderstood, however, that this disclosure is not limited to thespecifically described embodiments. Instead, any combination of thedescribed features and elements, whether related to differentembodiments or not, is contemplated to implement and practice thisdisclosure. Many modifications and variations may be apparent to thoseof ordinary skill in the art without departing from the scope and spiritof the described embodiments. Furthermore, although embodiments of thisdisclosure may achieve advantages over other possible solutions or overthe prior art, whether or not a particular advantage is achieved by agiven embodiment is not limiting of this disclosure. Thus, the describedaspects, features, embodiments, and advantages are merely illustrativeand are not considered elements or limitations of the appended claimsexcept where explicitly recited in a claim(s).

As will be appreciated by one skilled in the art, aspects of the presentdisclosure may be embodied as a system, method, or computer programproduct. Accordingly, aspects of the present disclosure may take theform of an entirely hardware embodiment, an entirely software embodiment(including firmware, resident software, micro-code, etc.), or anembodiment combining software and hardware aspects that may allgenerally be referred to herein as a “circuit,” “module,” or “system.”Furthermore, aspects of the present disclosure may take the form of acomputer program product embodied in one or more computer readablemedium(s) having computer readable program code embodied thereon.

Any combination of one or more computer readable medium(s) may beutilized. The computer readable medium may be a computer readable signalmedium or a computer readable storage medium. A computer readablestorage medium may be, for example, but not limited to, an electronic,magnetic, optical, electromagnetic, infrared, or semiconductor system,apparatus, or device, or any suitable combination thereof. More specificexamples (a non-exhaustive list) of the computer readable storage mediumwould include the following: an electrical connection having one or morewires, a portable computer diskette, a hard disk, a random access memory(RAM), a read-only memory (ROM), an erasable programmable read-onlymemory (EPROM or Flash memory), an optical fiber, a portable compactdisc read-only memory (CD-ROM), an optical storage device, a magneticstorage device, or any suitable combination thereof. In the context ofthis disclosure, a computer readable storage medium may be any tangiblemedium that can contain, or store, a program for use by or in connectionwith an instruction execution system, apparatus, or device.

A computer readable signal medium may include a propagated data signalwith computer readable program code embodied therein, for example, inbaseband or as part of a carrier wave. Such a propagated signal may takeany of a variety of forms, including, but not limited to,electro-magnetic, optical, or any suitable combination thereof. Acomputer readable signal medium may be any computer readable medium thatis not a computer readable storage medium and that can communicate,propagate, or transport a program for use by or in connection with aninstruction execution system, apparatus, or device.

Program code embodied on a computer readable medium may be transmittedusing any appropriate medium, including but not limited to wireless,wire line, optical fiber cable, RF, etc., or any suitable combinationthereof.

Computer program code for carrying out operations for aspects of thepresent disclosure may be written in any combination of one or moreprogramming languages, including: an object oriented programminglanguage such as Java, Smalltalk, C++, or the like; and conventionalprocedural programming languages, such as the “C” programming languageor similar programming languages. The program code may execute asspecifically described herein. In addition, the program code may executeentirely on the user's computer, partly on the user's computer, as astand-alone software package, partly on the user's computer and partlyon a remote computer, or entirely on the remote computer or server. Inthe latter scenario, the remote computer may be connected to the user'scomputer through any type of network, including a local area network(LAN) or a wide area network (WAN), or the connection may be made to anexternal computer (for example, through the Internet using an InternetService Provider).

Aspects of the present disclosure have been described with reference toflowchart illustrations, block diagrams, or both, of methods,apparatuses (systems), and computer program products according toembodiments of this disclosure. It will be understood that each block ofthe flowchart illustrations or block diagrams, and combinations ofblocks in the flowchart illustrations or block diagrams, can beimplemented by computer program instructions. These computer programinstructions may be provided to a processor of a general purposecomputer, special purpose computer, or other programmable dataprocessing apparatus to produce a machine, such that the instructions,which execute via the processor of the computer or other programmabledata processing apparatus, create means for implementing the functionsor acts specified in the flowchart or block diagram block or blocks.

These computer program instructions may also be stored in a computerreadable medium that can direct a computer, other programmable dataprocessing apparatus, or other devices to function in a particularmanner, such that the instructions stored in the computer readablemedium produce an article of manufacture including instructions whichimplement the function or act specified in the flowchart or blockdiagram block or blocks.

The computer program instructions may also be loaded onto a computer,other programmable data processing apparatus, or other devices to causea series of operational steps to be performed on the computer, otherprogrammable apparatus, or other devices to produce a computerimplemented process such that the instructions which execute on thecomputer or other programmable apparatus provide processes forimplementing the functions or acts specified in the flowchart or blockdiagram block or blocks.

Embodiments according to this disclosure may be provided to end-usersthrough a cloud-computing infrastructure. Cloud computing generallyrefers to the provision of scalable computing resources as a serviceover a network. More formally, cloud computing may be defined as acomputing capability that provides an abstraction between the computingresource and its underlying technical architecture (e.g., servers,storage, networks), enabling convenient, on-demand network access to ashared pool of configurable computing resources that can be rapidlyprovisioned and released with minimal management effort or serviceprovider interaction. Thus, cloud computing allows a user to accessvirtual computing resources (e.g., storage, data, applications, and evencomplete virtualized computing systems) in “the cloud,” without regardfor the underlying physical systems (or locations of those systems) usedto provide the computing resources.

Typically, cloud-computing resources are provided to a user on apay-per-use basis, where users are charged only for the computingresources actually used (e.g., an amount of storage space used by a useror a number of virtualized systems instantiated by the user). A user canaccess any of the resources that reside in the cloud at any time, andfrom anywhere across the Internet. In context of the present disclosure,a user may access applications or related data available in the cloud.For example, the nodes used to create a stream computing application maybe virtual machines hosted by a cloud service provider. Doing so allowsa user to access this information from any computing system attached toa network connected to the cloud (e.g., the Internet).

The flowchart and block diagrams in the figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods, and computer program products according to variousembodiments of the present disclosure. In this regard, each block in theflowchart or block diagrams may represent a module, segment, or portionof code, which comprises one or more executable instructions forimplementing the specified logical function(s). It should also be notedthat, in some alternative implementations, the functions noted in theblock may occur out of the order noted in the figures. For example, twoblocks shown in succession may, in fact, be executed substantiallyconcurrently, or the blocks may sometimes be executed in the reverseorder, depending upon the functionality involved. It will also be notedthat each block of the block diagrams or flowchart illustration, andcombinations of blocks in the block diagrams or flowchart illustration,can be implemented by special purpose hardware-based systems thatperform the specified functions or acts, or combinations of specialpurpose hardware and computer instructions.

While the foregoing is directed to exemplary embodiments, other andfurther embodiments of the invention may be devised without departingfrom the basic scope thereof, and the scope thereof is determined by theclaims that follow.

What is claimed is:
 1. A computer program product for managing adatabase, the computer program product comprising a computer readablestorage medium having program instructions embodied therewith, theprogram instructions configured to, when executed on one or moreprocessors, cause the one or more processors to: structure a database tohave a first table having an encoded vector Index (EVI) and a secondtable, a first key of the first table related to a second key of thesecond table; create an entry locator in the EVI; and maintain anassociation between the second key of the second table and the entrylocator in the EVI.
 2. The computer program product of claim 1, whereinthe first key is a foreign key and the second key is a primary key. 3.The computer program product of claim 1, wherein the first table is afact table and the second table is a dimension table.
 4. The computerprogram product of claim 1, wherein maintaining the association betweenthe second key of the second table and the entry locator in the EVI isperformed in response to at least one of a maintenance to the secondtable, a query to the database, a temporal element, or a refresh period.5. The computer program product of claim 4, wherein the maintenance tothe second table includes at least one of an addition, a deletion, or achange.
 6. The computer program product of claim 1, wherein the entrylocator includes at least one of: a column of a symbol table; and arelative record number pertaining to the second key of the second table.7. The computer program product of claim 1, wherein maintaining theassociation between the second key of the second table and the entrylocator in the EVI includes keeping updated the entry locator in the EVIwith information pertaining to the second key of the second table. 8.The computer program product of claim 1, wherein maintaining theassociation between the second key of the second table and the entrylocator in the EVI reduces latency when the first table and the secondtable are separated by a significant distance.
 9. The computer programproduct of claim 1, wherein the EVI further comprises: a symbol tablefor indicating which code values are assigned to which key values of thefirst key of the first table; and a vector having a plurality of rowscorresponding in a one-to-one relationship with a second plurality ofrows in the first table whereby, for each row of the plurality of rowsin the vector, a code value located in the row serves to indicate that akey value of the first key to which the code value is assigned islocated in a corresponding row of the second plurality of rows in thefirst table.
 10. The computer program product of claim 9, wherein theentry locator indicates, for each key value of the first key, which rowof a third plurality of rows in the second table has a key value of thesecond key that corresponds with the key value of the first key.
 11. Acomputer program product comprising a computer readable storage mediumhaving program code embodied therewith, the program code configured suchthat when executed by one or more processors the program code causes theone or more processors to perform a method comprising: accessing anencoded vector index (EVI) for a fact table, wherein the EVI includes: asymbol table for indicating which code values are assigned to which keyvalues of a first key in the fact table; a vector having a plurality ofrows corresponding in a one-to-one relationship with a second pluralityof rows in the fact table whereby, for each row of the plurality of rowsin the vector, a code value located in the row serves to indicate that akey value of the first key to which the code value is assigned islocated in a corresponding row of the second plurality of rows in thefact table; and an entry locator for indicating, for each unique keyvalue of the first key in the fact table, which row of a third pluralityof rows in a dimension table has a key value of a second key thatcorresponds with the unique key value of the first key.
 12. The computerprogram product of claim 11, wherein the method further comprises:selecting a key value of the first key; using the symbol table toidentify a specific code value assigned to the selected key value of thefirst key; identifying at least one row of the second plurality of rowsin the fact table as having the selected key value by searching for rowsof the first plurality of rows in the vector having the specific codevalue; and using the entry locator to identify at least one row of thethird plurality of rows in the dimension table as having a key value ofa second key corresponding with the selected key value of the first key.13. The computer program product of claim 11, wherein the entry locatoris a column of the symbol table.
 14. The computer program product ofclaim 13, wherein relative record numbers for rows of the thirdplurality of rows in the dimension table are listed in the column of thesymbol table, wherein unique key values of the first key in the facttable are listed in a second column of the symbol table, and whereineach row of a fourth plurality of rows in the symbol table includes arelative record number and a unique key value of the first key wherebythe relative record number indicates that a key value of the second keyin the dimension table corresponding to the unique key value of thefirst key is located in a row of the third plurality of rows in thedimension table that corresponds with the relative record number.